Issue 49

L.. Malíková et alii, Frattura ed Integrità Strutturale, 49 (2019) 65-73; DOI: 10.3221/IGF-ESIS.49.07

Focused on Crack Tip Fields

Multi-parameter fracture mechanics: crack path in a mixed-mode specimen

L. Malíková, H. Šimonová, B. Kucharczyková Brno University of Technology, Faculty of Civil Engineering, Institute of Structural Mechanics, Veveří 331/95, 602 00 Brno, Czech Republic

malikova.l@fce.vutbr.cz, http://orcid.org/0000-0001-5868-5717 simonova.h@vutbr.cz, http://orcid.org/0000-0003-1537-6388 Barbara.Kucarczykova@vutbr.cz, http://orcid.org/0000-0002-7123-5099 P. Miarka

Academy of Sciences of the Czech Republic, Institute of Physics of Materials, v. v. i., Žižkova 22, 616 62 Brno, Czech Republic and Brno University of Technology, Faculty of Civil Engineering, Institute of Structural Mechanics, Veveří 331/95, 602 00 Brno, Czech Republic Petr.miarka@vut.cz, http://orcid.org/0000-0002-4953-4324

A BSTRACT . A mixed-mode geometry has been chosen to investigate a crack propagation using the multi-parameter fracture mechanics concept. The so- called Williams’ series expansion is used for the crack-tip stress field approximation. It has been shown that application of the generalized fracture mechanics concept can be crucial for materials with specific fracture behaviour, such as elastic-plastic or quasi-brittle one, when fracture occurs not only in the very vicinity of the crack tip, but also in a more distant surrounding. Then, considering the higher-order terms of the Williams’ expansion in fracture criteria (describing the crack stability and/or crack propagation direction) can bring more precise results. The coefficients of the Williams’ expansion must be calculated numerically (for instance by means of the over- deterministic method in this work) for each cracked configuration, which is very time-consuming, and the analysis is very extensive even for a few basic cracked specimen configurations. On the other hand, a suitable choice of the geometrical configuration of the cracked disc enables performing experiments only on the specimens that could prove the theory about the importance of using the higher-order terms. K EYWORDS . Crack-tip field; Multi-parameter fracture mechanics; Finite element analysis; Mixed-mode; Williams’ expansion.

Citation: Malíková, L., Šimonová, H., Kucharczyková, B., Miarka, P., Multi- parameter fracture mechanics: crack path in a mixed-mode specimen, Frattura ed Integrità Strutturale, 49 (2019) 65-73.

Received: 21.04.2019 Accepted: 25.04.2019 Published: 01.07.2019

Copyright: © 2019 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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